Conjuration is an advanced form and branch of Transfiguration, some of the most complex magic taught at Hogwarts School of Witchcraft and Wizardry. Conjurations are distinguished from the other branches of Transfiguration by their ability to transfigure the desired object from 'thin air'.

According to The Book of Spells by Miranda Goshawk, "for reasons that are still not fully understood ... two categories of creature are easier to conjure from nothing than any other: birds and snakes." The spell to conjure birds is called the Bird-Conjuring Charm, which suggests that Serpensortia might be called the Snake-Conjuring Charm.

Dangers

A frog-rabbit hybrid.

Many things can go wrong when attempting to conjure something from nothing, especially in the case of living creatures. If Conjuration is not performed exactly right or if the caster is simply messing around with Conjuring Spells, mistakes such as frog-rabbit hybrids can occur. The hybrids in question can be explainable by the magical law Principle of Artificianimate Quasi-Dominance. Things such as severed heads and indeterminate stumps can also occur, when the conjuration isn't exactly right, as well.

Miranda Goshawk, has written entries in the Standard Book of Spells series about the dangers of poor conjuration.

Known instances of Conjuration

"However, these brothers were learned in the magical arts, and so they simply waved their wands and made a bridge appear across the treacherous water."